Our invention relates to a method for solder splicing one conductor of a coaxial cable to a second wire and, at essentially the same time, grounding the other conductor of the coaxial cable. Our invention also relates to a closure which facilitates the splicing/grounding method.
The installation of a radio in an automotive vehicle typically involves the step of connecting an antenna wire to the inner conductor of a coaxial cable and grounding the braided outer conductor of the coaxial cable to the automobile body and frame. An accepted prior art technique involves the use of multiple crimping steps and the provision of protective plastic tubes as well as one or more soldering steps. Wires can be cut or damaged during the crimping operation and the soldering operation can result in electrical shorts.
Our invention simplifies the splicing of coaxial cable to wire as well as the grounding of the unspliced conductor of the coaxial cable. We provide a box-like closure of non conductive material, preferably injection molded plastic, having a floor, surrounding side walls and first and second covers which can be independently closed. A grounding bracket is combined with the closure such that a portion of the bracket projects through the closure floor to define the solder point for a grounding connection. The rest of the bracket is used to attach the closure to a vehicle body part. The covers are closed in sequence; the first cover is closed to hold the spliced wire prior to soldering and the second cover is closed after soldering to clamp and protect the coaxial cable.
According to our method, an end-stripped coaxial cable is placed in the closure, preferably press fit into one or more notches parallel to and proximate one of the side walls. The partially stripped braided outer conductor is pulled to one side and placed on an upstanding soldering member which is integral with the grounding bracket and which projects through the closure floor. At least part of the soldering member is preferably fork-shaped. An end-stripped insulated wire is also placed into the closure proximate and parallel to the side wall and in contacting alignment with the inner conductor of the coaxial cable. One of the two covers is closed on the wire to clamp it in place. Thereafter the wire and the inner conductor of the coaxial cable are soldered together and, at essentially the same time, the braided outer conductor of the coaxial cable is soldered to the upstanding soldering member. Thereafter the second cover is closed to clamp the coaxial cable in place.
Further in accordance with our invention we provide a closure for facilitating the method. The preferred closure comprises a plastic box with the embedded grounding bracket insert molded therewith. The covers are preferably hingedly attached to one side wall of the box in longitudinally spaced parallel positions. Each of the covers is preferably provided with a lateral extending clamping bar on the interior surface thereof. Means are formed integral with the box for defining coaxial cable and insulated wire receiving locations, these two locations being adjacent an outer longitudinal side wall and defined in the preferred embodiment by one or more notches and fork-shaped receiving areas. Also in the preferred embodiment an interior wall or partial wall is provided between the soldering points to reduce the likelihood of an inadvertent grounding connection between them. The soldering points are, therefore, laterally spaced and separated from one another by the interior wall.
As indicated above, the first or smaller of the two covers is preferably closed on the insulated wire to clamp it into position prior to soldering. The second cover is closed after the soldering operation to clamp the coaxial cable in place.